Lock-bottom pump



June 17, 1930. "R W. GUN ET A.

LOCK BOTTOM PUMP. i 4 l Filed De@n '7, 1927 5 sheets-sheet' l A Y 4 ll,l/ f Vvvvvv Ys Jaya/m'` June 17, v1930'. R. w. 'GUNN ET AL, l "1,764,075, I LOOK BOTTOM PUMP Filed Deo. 7, 1927 3 Sheets-Sheet 2.

June. 17, 1930. R5. W. GUNN ET AL LOCK BOTTOM PUMP Filed Dec.v 7, 1927 fly 7.

Patented June 17, 1930 UNI-TED lsTArlszs PAIENI OFFICE ROBERT W. GJLNN AND wILLsIE A. s. TIIOMIsomOE Los ANGELES, CALIFORNIA, As-

sIGNoEs, BY MEsNE AssIGNMENTsmO EMsCO DEEnICx a EQUIPMENT COMPANY, OE Los ANGELES, CALIFORNIA, AfCORPOEATION OE CALIFORNIA v LOCK-BOT'TOM PUMP Application med Decemberl 7, 1927. serial No. 238,265.

This invention relates generall `to deep i Well pumps, and is more particu arly concerned with pumps of the lock-bottom tirre- As is well known, a lock-bottom pump may be characterized as a full pump assembly, in-

cluding barrel and plunger, adapted 4to belowered bodily into the Well tubing after the latter has been set. One of the problems incident to the installation ofv a pump of `this` character isto accomplish a releasable thenl to be easily releasable when occasion arises for lifting the pump for inspection,

replacement or repair.

Heretofore, these releasable4 connections have usually involved grapple ngers or ex` panding mandrels -With their accompanying complications. lVhile arrangements 'of these kinds are ordinarily satisfactory asfar Oas positiveness of grip is concerned, they do not prove fully efficient. For instance, ifthe grapple fingers are of a nature to be moved positively into holding position beneath shoulders on the tubing, there must be pro-C vided means for restraining the fingers from such movement during their descension through the tubing to final position and then means must be provided to retract the fingers from holding position when it is desired to pull the barrel, this necessarily calling for complications in mechanism. The restraining mechanism is needful in order to prevent premature locking of the barrel and to prevent the fingers from contacting undesirably With the tubing or the joints thereof during descension or ascension of the barrel.

To overcome these conditions, as Well as others, We devised thel type of frictional lock disclosed in our copending application entitled Pump7 filed April 26, 1927, No. 186,- 681. In that application, We showed a gripping member in the form of a tube slit lon-- gitudinally at a point intermediate its ends, the tube being of such material that this slit ting provided a radially resilient portion. This portion was ada ted to be thrust or forced with friction-tig t fit into a restricted bore provided near .the lower en'd of the tubing. The locking was thus accomplished Without the use of grapple fingers with vfreely 12projecting ends and Without the necessity O any auxiliary mechanism either for moving the gripping members into locking engagement with the tubing or for releasing them from such locking engagement.`

While the last mentioned type, lof connection has 'been found entirely suitable under certain conditions, there are some situ- L ations Where-it is desirable that the gripping member engage the tubing with greater frictional force than is practicable through the use of a tube slitted in this fashion, it being obvious that -if a tube so slitted be sufficiently i sturdy to withstand the strains to which it is exposed during and after insertion, it is inherently limited as to the amount of weakening it may undergo in providing for a desirable degree of radial, resilient movement. Furthermore, once such a member had been fashioned for installation in a given pump, it couldv not be adjusted Afor adaptation to variations in different pumps, except that' itihad a 'slight inherent capacity to adjust -itself wi-thin a small range.

Therefore, ,it may be considered as-anY object of thepresent invention to provide a gripping member having the advantageous.

points of the device shown in aforesaid co-Y pending application, as'regards absence of freely projecting grapple fingers, actuating mechanism, etc., and having, in addition,

much greater inherent capacity for radial expansion and contractionl and thus be adapted to` engage the tubing with vmuch greater effective `frictional force, though it need neverv engage lthe tubing during ascension or descension of the pump barrel theiethrough. Furthermore, it is capable of adjustment Within a comparatively large i range to adapt it to varying situations.v l

Another object of four invention is to provide a gripping combination in which fingers v areprovided having an appreciable inherent tendency to spring outward from the supporting means on which they are carried,-

` being adapted to engage the free ends of the fingers to limit their outward, movement.; The fingers are provided with gripping portions which protrude beyond the keeper.

Another object of our invention is to provide a combination as just mentioned which includes adjusting means whereby the fingers' may be adjusted relative to the keeper in order that the limiting of the outward movement of the free ends of the fingers may be varied.

Our invention may provide either a plu.; rality of fingers or may provide but a single finger.

Another object of the invention is to pro- -vide a combination of the character. 'dev scribed which includes'a pump barrel adapttion `in connection with the'tubing at ed to be installed in a well tubing, a grip'- ping member near the lower end of the barr-'el for holding the barrel releasably longitudinally positioned in the tubing, means near the upper'end of the barrel for supporting the weight of the barrel and including a closure on the barrel adjacent to the gripping means for forming a seal between the tubing and the barrel.

Another object of our invention is to pro- Y vide a gripping combination for lock-bottom pumps and the like, iny which gripping means designed' for releasably gripping a part, andisealing meansi'designed for forming fa seal between the partv and a supporting means,are both retainedv on a supporting means.

Another l,object of our invention is to provide a gripping combination which includes grippin members adapted to engage a part so that t ve gripping means and any construction secured to it releasably-longitudinally positioned in the part, and a sealing means' in the form of a cup leather for forming a seal between the combination and the part which it engages.

. The manner in which we accomplishithe above, as well as other objects and novel features of the'invention, may be pointed out to vbetter advantage in connection with the following detailed description, reference being: 'had to the accompanying drawings, in

which: A. Fig. 1 shows an embodiment of our invelxlibottom o f a well;` A j Fig. 2 is an enlarged fragmentary section, partly in elevation, on line 2-2 of Fig. 1;

Fig. 3 is an enlarged fragmentary section on line 3--3 of 'Fig.\1, parts being shown in elevation;

Fig. 4 isa section on line 4-4 of Fig.- 3; Fig. 5 i's a detached section of the barrelcarried gripping element, one of the spring fincgers being broken off near its anchored en y Fig. 6 is an enlarged section on line66 at 10 usualtubing adapted to be lowered into a wellpreparatory to pumping fluid therefrom. l,Secured tothe lowermost end ofthe tubing through coupling 11, is the tubular shell'12. Broadly, it will be understood'that shell 12 may beconsidered a part or extension of the well tubing, proper, particularly since it maybe made up of standard tubing stock and needs no special vpreparation excepth cutting to proper length.

Hereinafter we will refer to section 12 as a shell in order more clearlyto locate various elements, but we refer to this section as a p artof the tubing in the appended claims.

As a matter of convenience and economy, coupling 11 'is also adaptedv to co-operate with a member carried by the pump, generally indicated at 13, in a manner to seal ofiI or form a {luid-tight closure between the tubing and pump, though it will be understood this is not limitative on the invention since the sealing member may be carried ,by the tubing other than throughcoupling' 11. Coupling 11 is shown in the form ofa sleeve having a central internal annularange 14a .functions as a gripping member adapted to receive a gripping member carried by the pump. While this portion may be an integral part of shell 12,'preferably it is in the form of a tubular shoe 18, lthe connection between shell and shoe preferably being through screw threads 19. Shoe 18 has an internal annular flange 20 which is of considerable longitudinal extent and defines the cylindric and relatively restricted'borc 21, said bore being of lesser' diameter than that of shell 12. The upper end of flange 2O is relieved at 22 to provide a flaring mouth 22a for bore 21, the curved or inclined walls defining this flaring mouth providing means for guiding the end of the pump into the restricted bore.

Pump 13 includes working barrel 23 havloo llO

ing at its upper end a cap member 24, and

near its-lower end the standing valve and gripping member 26.l We have here shown member 24 asbeing made up in such a 'man ner that-it has several functions, though it will be understood our invention, considered broadly, is not limited to this particular structure. Member 24 is made up ofthe tubular, cylindric body portion 27 having at its lower end a threaded portion 28 Whereby connection is made to'barrel 23, an enlarged collar portion 29, and a' downwardly and inwardly tapering portion .30 between portions 29 and 27, the portion 30 providing a conical, annular'seating face 31 which is complementary to sealing face 16 with which it is adapted to engage when the pump 'is fully assembled with the tubing.

Extending upwardly from portion 29 are posts 32 which support head -v33the latter having an axial bore 34 adapted to'take pump rod 35, said rod being ofv such a diameter that there is left ample annulardlea'r- ,ance 36 between itand portion 27 to'allow parent hereinafter.

' the free passage of fluid from barrel 23 up wardly about the rod and outwardly between posts 32 to the interior of tubing 10 at a point above' the pump. The top yof head 33 presents an upwardly facing shoulder 37, while the lower end of member 24 presents a downwardly facing shoulderl 38,

shoulders 37 and 38 thus providing -longitudinally spaced and oppositely facing abutments, the purpose of which will be made ap- It will be seen that head 33 provides a guide member for centering the pump rod in the barrel, and also serves asA an out-board bearing to reduce the chance of the rod being bent or sprung.

Connection between standing valve 25 and barrel 23 is made through a usualdoubleended coupling 40, the tubular housing 41 of the standing valve comprising, inv effect,

a downward continuation of the barrel. Coupling 40 has the usual axial bore 42 to allow the free passage of fluid therethrough and carries a usual bridge or bumper 43 spaced from the lower end thereof to provide a stop for limiting the upward movement. of the valve ball or stopper 44.

W'hile this is in no way controlling on the invention, gripping member 26 and standing valve 25 are preferably connected through a nipple 45, said nipple and the tubular mandrel 446, which latter makes up a portion of gripping lmember 26, forming, in effect, an extension of barrel 23.

The upper end of nipple 45 is adapted to be threaded into connection with barrel 23 at 47, the end of the nipple'presenting a shoulder 48 which faces-and is spaced below the downwardly facing shoulder 49 pre- -sented by the internal annular flange 50 on the sleeve 41, these shoulders taking between them the annular flange 51 on valve seat 52 to osition the latter within said sleeve.

v Mandrel 46 is threaded at its upper and lower endsas at 53 and 54, respectively, an external annular flange 55- being provided about the mandrel just beneath. threaded f portion 53p W'hile this flange has certain functions in connection with the operation of the gripping member, this function will be' described at a later point, but mention will here be made that it provides an up-` wardly facing annular shoulder 56, preferablysomewhat arcuate as viewed in crosssection (Fig. 6) against which a cup-leather or washer 57 is adapted to be pressed by the lower end 58 of nipple 45, the latter being in. threaded engagement with portion .Preferably, the lower end of nipple 45 is .annularly relieved as at 59 to leave an annu- .lar space 60 between it and the annular flange 61 ofthe cup-leather, this flange en gaging the inner peripheral wall of shoeliange 20 when gripping member 26 is fully ,l

entered in gripplng member 18, as shown in Fig; 6. At such a time the face 31 of .member 24 is in tight engagement with face 16 of coupling 1l, and it will be seen that members 24, and 57 thus close off the oppositeV ends of the annular space S betweeny shell 12 and the pump barrel, preventing appreciable leakage of iiuid into said space from above or below the pump barrel. The entrance of sand `between the shell and barrel is thus prevented, and the. danger of sanding in the pump is avoided, a feature of'obvious advantage. However, these se'all ingmembers which provide' for fluid-tight engagement between the shell and pump are of a nature to bereadily released when occasion arises for pulling the pump.

Before proceeding to a detailed description of gripping member 26 and merely considering it as an element which is radially 'resilient and adapted` t0 be forced with friction-tight fit into shoe 18, we will describe the more or less conventional ump plunger, the ymethod of utilizing this for forcingthe lgripping member home and for releasing it from holding engagement, and will outline the .normal operation of the pump.' We

will then go on to discuss in vdetail the prel fel-red and improved type of gripping memlOtw -llO

rods 69; and it will be .noted that coupling 68 presents a downwardly facing annular Vshoulderl 70 about rod 35 which is longitudinally spaced along the rod`from the upwardly facing shoulder -71 presented by workingvalve 65, thel longitudinal. spacing determining the extent of relative longitudiof the plunger during normal pump actua-I nal movement allowed b etween the pump barrel and plunger 63, this extent of movement being sufficiently: greater than the l length of the working stroke of the plunger to permit full, unintercepted reciprocation tion.

The' tubing 12, with its shoe 18 in place, is first set within the Well. The fully assembled pump is then attached to the line of sucker rods and lowered in the usual manne-r, the pumpduring its descension be- 0f held from droppingfrom the rod due 1n tobthe fact that shoulder 38 of member 24 rests upon shoulder71 of valve 65. As soonas gripping member 26 comes into end engagement with shoe 18 the pump comes to l rest while the sucker rods and 'elements eariied thereby continue downwardly until shoulder-70 of coupling 68 strikes shoulder 37 of member 24. The weight of th'e sucker rod line is then imposed upon thepump and -forces thelatter downwardly to enter member 26 in restricted bore 21. If said member 26 does not immediatelyenter said shoe-bore,

the sucker rod line may be lifted and dropped repeatedly (the lift being less than enough to unseat the gripping member from the shoe) the gripping member on the barrel thus being hammered or driven home by repeated impingementof shoulder 70 upon shoulder 37.

sucker and pump rods,

f passage.

raised through the I fluid flows through mandrel 46, nipple 45,'lifts ball 44 and passes into the bore ofthe barrel while the When the plunger is column of fluid above the closed workingA Valve 65 is lifted andpasses out the upper end of the barrel through bore .36 and between posts' 32 to the tubing bore above the pump. On the subsequent Adown-stroke of the plunger, ball 44 is seated, and the fluid thereabove is forced through the bore of the plunger stem 63 into the barrel bore thereabove, lifting stopper 66 of valve 65 in its When itv becomes necessary or. desirable to pull the pump, the sucker rods are moved upwardly until valve engages vshoulder 38, whereupon continued upward ull on the sucker rods draws gripping mem er 26 1ongitudinally free from the shoe 18.

lVe will now describe the particular makeup of the preferred embodiment of gripping member 26, though it will be understood the invention, considered in its broader aspects, is not limited to all these particularities. Gripping member 26 includes the tubular mandrel. 46, heretofore described, and a sleeve 'encircling this mandrel and .having a radially resilient portion R.

, In order to point out the characteristics of this -sleeve,`it will be helpful to consider the procedure in making. it up, though 1t will be understood, of course, that the inveny ,tion is in no way limited by this description of procedure. During this discussion, it will be assumed that the mandrel 46 is utilized as a supporting medium for the sleeve during certain machining operations thereon, but it will be immediately apparent that this utilization is not essential, since equivalent supporting means `especially adapted for shop use may be utilizedin lieu of the mandrel, and the finished sleeve may beA bore of shell 12. The free ends of the lingersv are vthen spread apart a considerable distance, for instance, to the positions shown in dotted lines in Fig. 5, the diameter of the -slitted portion from a point near its lower end to the finger tips thus being made appreciably greater than the diameter of restricted bore 2l.` The sleeve, in this condition, is`

then hardened and tempered, giving resilient characteristicsl to the fingers, they lhaving an' inherent tendenc to remain in the dotted' line 'position of ig. `5. The slitted portion Rv of the sleeve may now be considered as radially resilient.

The sleeve is then threaded on mandrel 46 (or upon an equivalent member, as men` tioned above) it being noted that the underside f ilarwe- 55,-which side faces the free end of the ngers,`is undercut as at 78, the flange thus having an annular Wall or extension 79 depending from the body portion thereof and overhanging the body portion of the mandrel in annularly spaced relation. While this undercutting may rovidean in wardly facingshoulderBO ofj any suitable form, preferably, shoulder 80 inclines downwardly and outwardly from the body portion of the mandrel, thus giving conical- 'characteristics to undercut.78. Theupper ends of fingers 77 preferably'have been preformed to provide tapereduextremities or tips 81,v the taper of the finger tips being substantially complementary to ihe'incline vof wall 80 when the fingers are in the position of Fig. 5. f

With 'the fingers then radially compressed lll) the fingers against movement from the position to which they have been sprung towards the dotted line position. The mandrel and sleeve are .threadably adjusted until, at a point somewhat above the Vbases of the fingers, for instance at the point b, the slittedl portion of the sleeve is of somewhat greater diameter than the restricted bore 21 of shoe 18. The sleeve and mandrel are mounted in a grinder or similar machine, and the vfin-gers are ground down until the diameterof the major portion (for instance from to b) of the radially resilient portion is just the diameter of restricted bore 21, the' fingers thus being given true, arcuate outer or seating faces F of considerable longitudinal extent which, when the fingers are spread just enough to fit within the restricted bore of the shoe, will be complementary to the wall defining said bore. In this condition the fingers still have very appreciable inherent tendency to spring outwardly; in fact, they may have a tendency to spring apart a distance greater than the diameter of the bore of the'tubing. The

' gripping member lis then in the condition of Fig. 5, it being apparent that the inner faces (Z of the fingers incline with respect to the axis A, that the outer faces from c to b are parallel with face (l, and that tlieouter, arcuate faces from a-b are parallel with axis A. The radially resilient portion when in the condition of lFigs. 5 and 6 is thus of uniform diameter throughout its effective extent a-ZL The reason that the radially resilient portion is of uniform diameter throughout the length `a-b and the reason that these arcuated faces are parallel tot the axis A is that the assembly shown in Fig. 5 has been placed in a lathe and the surface from a to?) has v'been turned so that a true cylindrical surface is obtained. It is true, therefore, that the'plane of the surface @,-b is parallel to the axis A.

lVhen the operations just described have been completedon the assembly shown in Fig. and the parts are still in the `positions shown in F ig. 5, the diameter defined by the' face af--b is the same `diameter as the restricted bore 21. It is therefore obvious that were the assembly entered into the bore 21, lit would have no gripping effect.

As we have already pointed out, there is a tendency for the spring fingers to occupy positions indicated by dotted lines in Fig. 5, and the reathenV son that these fingers do not occupy the posii tion shown by dotted lines is that the ends 81 of the fingers engage the wall y78 of the keep;

er fiange 55. Before installing theiassembly of Fig. 5 onto the barrel which must be locked in the tubing, the sleeve is rotated relative to the mandrel 46 sothat it is advancedawayfrom the flange 55. This pro` duces a relative movement betweenthe fingers 77 and the flange 55 with the result that vonly the extreme end of each finger 77 will engage the lower and outer part of the wall or face 78.

It will be obvious that this adjustment which we have just explained permits `the upper ends of the fingers 77.to swing outward with the result that the cylindrical face a-b is of larger diameter than the cylindrical bore 21. At this time the surface w-b is not truly cylindrical but is conical, being larger in diameter at its upper end than at its lower end because of the fact that thel upper endsof the fingers 77 swing outward more than the lower ends thereof.v -Preferably, however, the spread allowed to the fingers by the keeper fiange isnot sufcient to allow them to contact with shell 12 or tubing 10 as the pump is lowered or raised therethrough, and it will be seen that during such raising or lowering the keeper flange 55 not only restraiiis the fingers from excess outward movement, but also overlies the free ends of the fingers so they cannot ,engage with the tubing orjoints therein dur ing ascension or descension of the pump. Flange 55 is, of course, of less diameter than the boreof shell 12, and preferably, though not necessarily, is of less diameter than bore 21.' l

The last-described conditioirof sleeve 75 is illustrated in2 Fig. 7,',it being noted that flange 55 is holding the fingers from spreading outwardly into contact withV shell 12 and that the diameter of the radially resilient portion of said sleeve is greater than' the diameter of bore 21, though the effective extent of said portion is of less diameter at its lower end than at its upper. Now itwill be seen that though the fingers have a great capacity and tendency for radial expansion and are therefore capable of exerting great force against shoe 18 when they finally are moved into engagement therewith, they have not the detrimental characteristics of widely spread fingers; and it will be further seen that v'diie to the tapering characteristics of the finger ends and walls 80, the sleeve and mandrel may be adjusted longitudinally to lvary finely the extent of radial compression needed to enter the gripping member within justment provides for the setting of the sleeve -so it may be adapted to be entered in shoes of'different effective internal diameters. While the adjustment of the fingers is izo shoe 18. Further, it is obvious that this adshown here as accomplished byrelative movement of themandrel body and sleeve,

, it is obvious that the adjustment may be considered as accomplished by relative movement of the fingers and keeper flange and any method of employing such relative movement lies within the scope of our claims. Forinstance, this idea may be carried out as shown in Fig.. 8, wherein mandrel 46a is in the form of a pipe having threads 53)a and 5.4a at its upper and lower ends, respectively, flange 55"a being in the form of a collar threadably engaging the pipe at 53a. Sleeve 7 5a is then adapted to be secured to the pipe against longitudinal move-ment, as by pin P, and adjustment of spring fingers 77 is had by threading the collar 55EL along the pipe in an obvious manner. Nipple El acts through cup leather 57a to hold the collar in adjusted position. l

In Fig. 7 the gripping member is shown in the condition it occupies just prior to its entry to the shoe. It will be seen that when the barrel and hence mandrel 4G is pressed downwardly, as described above, lingers 77 will engage wall 22, be thereby broughtradially inward, and finally come to rest in the position of Fig. 6,' it being noted that the ends 810i the fingers are then clear of flange 55,v and that due to the pre-formation of -the outer faces F of the fingers, these bearing or gripping faces have full, true cylindric fit of appreciable longitudinal extent with the defining wall of bre 2l, with obvious advantage. Due to the inherent tendency ofthe fingers to spread apart, or, expressed otherwise, the inherent tendency of' the resilient portion of the sleeve to expand, the fingers have such a friction-tight fit with the shoe' that accidental, longitudinal separation of the barrel and tubing is effectively resisted.

It will be seen that though it was necessary to compress the-radially resilient portion only slightly to enter member 26 in the shoe, the tendency of said portion to expand is as great as though the lingers had been .moved in from the dotted line ositions of Fig. 5. Also, due tothe inclination of faces F, entrance of the fingers to the restricted bore is accomplished with comparative ease. lVhen the pump is pulled, as described above,vthe fingers are withdrawn from the restricted bore and as soon as they clear the shoe, they are caught by flange as in Fig. 7 so they will b e held clear of thetubing.

As a convenient means for holding sleeve from backing down from adjusted position, a collar 83 may be threaded on mandrel 46 therebelow, this collar also providing means for coupling a tubular gas anchor 84 -to the mandrel. In this manner the bore of the gas anchor is put in communication with the bore of the plunger through mandrel v46, nipple 45 and sleeve 4l, there being no latwel openings to the tubing bore through these members which are intermediate thel I mandrel, -a sleeve encircling the mandrel,

said sleeve being slit longitudinally from one end thereof toprovide a plurality of spring fingers forming together a radially resilient portion of the sleeve, said fingers having an appreciable inherent tendency to spring radially away from the mandrel at their free ends, and a radiall'y extending keeper member on the mandrel adapted to engage the free ends of thelingers to limit outward radial movement of said fingers, said fingers having gripping portions which extend radially beyond the keeper.

2'. A gripping member for lock-bottom pumps and the like, embodying a tubular mandrel, a sleeve encircling the mandrel, said sleeve being slit longitudinally from one end thereof to provide a plurality of spring fingers formingtogether a radiallyresilientA portion of the sleeve, said fingers having an appreciable inherent tendencyto spring radially away from the mandrel at -their free ends, and a radially extending keeper member on the mandrel, said mandrel and sleeve being relatively movablev longitudinally to engage the keeper with the Afreeends of the lingers to limit outward radial movementA of said fingers, said fingers having gripping portions which extend radially beyond the keeper.

3. A grippingA member for lock-bottom pumps and the like, embodying a tubular mandrel, a sleeve encircling the mandrel,

relative longitudinal movement, said sleeve being slit longitudinally from one end thereotto provide aplurality of spring lingers forming together a radially resil'ient`por- -said mandrel and sleeve being capable of tion of the sleeve, said fingers having an pumps' and the like, embodying' a tubular mandrel, a sleeve encircling themandrel,

' said' sleeve being slit longitudinally lfrom one end thereof to provide a, plurality of spring fingers forming together a radially resilient portion of the sleeve, said fingers having an appreciable inlierent.tendency 4to spring radially away from the mandrel at their'free ends, and a radially extending keeper member on the mandrel adapted to engage the free ends of the fingers to limit outwardradial movement of said fingers.--

5.- A gripping member for lock-'bottom pumps and the like, embodying a tubular mandrel, a sleeve encircling the mandrel, said sleeve being slit longitudinally from one end thereof to provide a pluralit of spring fingers forming together a radially resilient portion of the sleeve, said fingers having an appreciable inherent tendency toV spring radially away from the mandrel at f their free ends, and a radially extending keeper member on the mandrel adapted to engage Vthe free ends of the fingers to limit outward radial movement of said fingers, said fingers having arcuate gripping faces of appreciable longitudinal extent.

6. gripping member for lock-bottom pumps and the like, embodying a tubular lmandrel, a sleeve encircling the mandrel, -said sleeve ,being slit longitudinally from one end thereof to provide a plurality of spring lingers forming together a radially resilient portion of the sleeve, said fingers having an appreciable inherent tendency to spring radially away from the mandrel at their free ends` and an annular flange on the mandrel and having a depending portion adapted to overhang the free ends of the fingersv and thereby limit outward radialv movement thereof.

T. A gripping 'member for lockebottom pumps and the like, embodying a tubular mandrel, a sleeve encircling the mandrel.,

said sleeve being slit longitudinally from one end thereof toprovide a plurality ,of

` spring fingersvforming together a radially resilient port-ion of the sleeve, said fingers having an appreciable inherent tendency ton spring `radially away from the mandrel lat their free ends, and an annular flange on the mandrel and spaced from one end thereof, said flange having a depending portion at one side adapted to Aoverhang the free ends -f of4 the fingers and thereby limitoutward radial movement thereof, and a cup washer about the mandrel at the other side off the flange and of greater diameter than the flange.

- 8. A,gripping member for lock-bottom pumps and the like, embodying a tubular mandrel, a sleeve encircling the mandrel, said sleeve being slit longitudinally from lone end thereof to` provide a plurality` of spring fingers forming together a radially resilient portion of the sleeve, Said fingers f f having an appreciable inherent tendency to spring radially away from the mandrel at .their free ends, and an annular flange von the mandrel and spaced from one end thereof, said flange having a dependingportion at one side adapted to overhang the 'free ends of the fingers andtherebylimit outward radial movement thereof, a cup washer aboutthe mandrel at the other side of the flange and of greater diameter than the flange, and means for maintaining the wash- Aer seated on the flange.

9. `In combination, a well tubing, a pump barrel within and annularly spaced from the tubing, a gripping member carried bytlie barrel near its-lower end and adapted to hold the barrel re'leasably longitudinally positioned within the tubing bore, means near the upper end of the barrel providing a sand-tight closurebetween th'e tubing and barrel, and independent means on the barrel above but adjacent tothe gripping member providing a'closure between the tubing and barrel.

10. In combination, a well tubing whose bore has near its lower end a portion of restricted-diameter, a pump barrel adapted to be lowered to position through the tubing bore', a radially-resilient gripping member on the barrel, said member having an inv herent capacity and tendency *to expand 'radially to a diameter appreciably greater than that of the restricted bore portion, and

vmeans on the barrel adapted to limit the eX tent of radial expansion of said member below that to which itis inherently capable' of expanding though allowing said ,member predetermined vposition in a manner to hold'y the'barrel releasably in that position, and means on the barrel adapted to engagesaid fingers during movement of the barrel to said position and limit their outward movement to a diameter less than the internal diameter of said tubing. gt,

l2. The combination of a pump tubing having a seat of reduced diameter therein, a pump barrel adapted to be loweredthrough the tubing to a predetermined positiontherein, fingers carried by the barrel and having an inherent tendency to spring radially out- .i

f keeper; and adjusting means whereby saidv .finger may be adjusted relative to said keeper Ain order that the limiting of the outward wardly therefrom, said fingers being adapted to engage said'seat by virtue of said tendency when the barrel is in said predetermined position in a manner to'hold the barrel releasably inthat position, and means on the barrel adapted to engage the tips of said fingers during movement of the barrel to said position and limit their outward movenient to a diameter less than the internal diameter of said tubing. 4

13. The combination of al pump tubing having a seat of reduced diameter therein, a pump barrel adapted to be lowered through the tubing to a predetermined position therein, expansible fingers carried by the barrel and adapted to engage said seat by virtue of expansionv when the barrel is in said position and thereby hold the barrel releasably in that position, and means on the barrel adapted to engage the tips of said fingers during movement to. said barrel to said position for limiting the extent of fingerexpansion to a diameter less than the internal diameter of -said tubing. 4

14. A gripping combination for lock-bottom pumps and the like comprising: a supporting means; a spring finger supported by said supporting means, one end of said spring finger being attached to said supporting means and the other end being free to move inward and outward, said finger having an appreciable inherent tendency to spring outward from said supporting means at its free end; and a keeper carried by said supporting means adapted'to engage the free end of the finger to limit Outward movement of said finger, said finger having` a gripping portion which extends outward beyond said keeper. v

15. A gripping combination for lock-bottom pumps and the like comprising: a supporting means; a spring linger supported by said supporting means, one end of said spring finger being attached to said supporting means and the other end being freevto move inward and outward, said finger having an appreciable inherent tendency to spring outward from said supporting means at its free end; a keeper carried by said `supporting means adapted to engage the free end of the finger to limit outward movement of said finger, said finger having a gripping portion which extends outward beyond said ymovement of the free end of the finger may be varied.

16. A gripping combination for iock-bottom pumps and the like comprising: a sup-l porting means; va plurality of spring fingers .supported by said supporting means, said fingers having free ends and having an inherent tendency to spring outward from said I' supporting means at the free ends; a keeper carried by said supporting means adapted to engage said free endsto limit the outward movement, said fingers having gripping portions which extend outward beyond said keeper; and adjusting means whereby said fingers may be adjusted relative to said keeper in order that the limitingof the outward movement of the free ends of saidv fingers may be varied.

17. In combination: a well tubing; a

pump barrel within and annularly spaced from said tubing; a gripping member carried by said barrel near its lower end and adapted to hold said barrel releasably longitudinally positioned in said tubing; means near the upper end of said barrel `for sup-v means near the upper endV of said barrel for supporting the weight of said barrel; and an independent closure on said barrel adjacent said gripping means forming a seal between said tubing and said barrel. l

19. A gripping combination for lock-bottom pumps and the likecomprising: a central supporting means; a gripping means carried by said supporting means, said gripping means being designed for i'eleasably' gripping a part; and an independent sealing means on said supporting means for forming a seal between said supporting means and said part.

20. A gripping combination for iock-bottom pumps and the like comprising: a supporting means; a spring finger supported by said supporting means, one end of said spring lfinger being attached to said supporting means and thev other end .being free to move inward and outward, said finger having an appreciable inherent tendency to. spring outward from said supporting means at its free end; a keeper carried by said supporting means adaptedto engage the free end of the finger lto limit outward movement of said finger,I said finger having a gripping portion vwhich extends outward beyond said a well tubing;l a l keeper; and sealing means carried by said 1 supporting means.

21. A gripping combination for lock-bottom pumps and the like comprising: a supporting means; a springl finger supported by said supporting means. vone end of said spring finger being attached to said'supporting means and the other end being free to move inward and outward, said finger hav- .ing an appreciable inherent. tendency to spring outward from said supporting means at its free end; a keeper Carried by said supporting means adapted to engage the free end of the finger to limit outward movement of said linger, said linger having a gripping portion which extends outward beyond said keeper; adjusting means whereby said finger may be adjusted relative to said keeper in order thatthe limiting of the outward movement of the free end of the finger may be varied; and sealing means carried by said supporting means.

22. A gripping combination for lock-bottom pumps and the like comprising: a supporting means; a plurality of spring fingers supported by said supporting means, said fingers having free ends and having an inherent tendency to spring outward from said supporting means at the free ends; a keeper carried by said supporting means adapted to engage said free ends to limit the outward movement, said fingers having gripping portions which extend outward beyondsaid keeper; and sealing means Carried by said supporting means.

23. A gripping combination for lock-bottom pumps and the like comprising: a sup porting means; a plurality of spring fingers supported by said supporting `means, said fingers having free ends and having an inherent tendency to spring outward from said supporting means at the free ends; a

keeper carried `by said supporting means adapted to engage said free ends to limit the outward movement, said lingers having gripping portions which extend outward be- .Y yond said keeper; adjusting means whereby y said fingers may be adjusted relative to said keeper in order that the limiting of the out ward movement of the free ends of said fingers may be varied; and sealing means carried by said supporting means.

In witness that We Claim the foregoing we have hereunto subscribed our names this 16th. day of November, 1927.

WILLSIE A. S. THOMPSON. ROBERT W. GUNN. 

